The present invention relates to a grinding machine having a rotatable, substantially circular segmented head which receives grinding segments on its circumference, as well as a cooling-water feed, extending to the inner side of the grinding segments.
The invention relates in particular, but not exclusively, to surface grinding machines with a vertical drive shaft which receives the segmented head at its lower end, the grinding segments being fastened to the circumference of said head. As prior art, reference is made to German Patent Application (unexamined) No. 22 48 174.9 U.S. Pat. No. 1,797,526 and Swiss Pat. No. 242 897.
Heavy-duty grinding machines having a drive power of for instance, up to 200 kW operate today with a volume, per unit of time, of metal removed which makes it possible to eliminate prior planing and milling operations and to complete a workpiece directly on a grinding machine. Such high drive powers can, however, be meaningfully employed only if sufficient cooling and lubrication are provided. Otherwise, losses in quality of the workpiece can occur as a result of excessive thermal stressing of the workpiece and the pores of the grinding segments can become clogged by abraded material and thus impair the effectiveness of the grinding segments.
For this reason it is of particular importance that cooling water be fed, in the largest quantities possible directly into the region between the workpiece and the grinding segments. Due to the considerable speed of rotation of the segment head, there is the danger that the cooling water fed will become eddied and form a mist which is subject to considerable resistance to flow and therefore can be fed only at a low rate of passage.
Applicant's aforementioned German patent application No. 22 48 174.9 provides substantial improvements along this line. The object of the invention is further to increase the feed of cooling water to the working region.